Porphyritic Basalt or Diabase with Plagioclase Phenocrysts
Porphyritic Basalt or Diabase; Mineral: Plagioclase Feldspar
Igneous
Category
Mineral (Native Element)
Browse mineral (native element) specimens identified by the Rock Identifier community.
Learn about Mineral (Native Element) in the encyclopedia
View all →
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
mineral
Quartz on Host Rock
Silicon Dioxide (SiO2)
Mineral Specimen
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (SiO₂)
Mineral
Tumbled pink quartz (probable rose quartz)
Quartz, silicon dioxide (SiO₂), commonly colored by trace elements and microscopic inclusions
mineral
Polished blue banded agate slice
Chalcedony (microcrystalline quartz), SiO₂, commonly with trace iron and other coloring elements
mineral
Shale
Shale
sedimentary
Black Tourmaline (Tumbled)
Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)4)
mineral
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
mineral
Jewelry Chain with Blue and Clear Gemstones (Likely Cubic Zirconia)
Cubic Zirconia (ZrO₂), Silver or White Gold/Platinum Alloy
Mineral (synthetic) and Metal (precious/base)
Granite
Granite (a felsic intrusive igneous rock)
Igneous
Chrysocolla
Hydrated copper phyllosilicate, Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)
mineral
Schist
Schist (various mineral compositions)
metamorphic
Schist
Schist (various compositions)
metamorphic
Serpentinite (Serpentine Rock)
Serpentinite is a rock composed of one or more serpentine group minerals, chiefly antigorite, chrysotile, and lizardite, with the general formula (Mg,Fe)3Si2O5(OH)4. Often includes other minerals like magnetite, talc, and chromite.
Metamorphic Rock
Smelter Slag
Anthropogenic Silicate Slag
igneous
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Black Tourmaline
Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)4)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Goldstone
N/A (Synthetic Glass with Copper Inclusions)
Manufactured Glass
Yellow Quartz (Citrine-colored Quartz Pebble)
Silicon Dioxide (SiO2)
mineral
Milky rose quartz
Quartz, silicon dioxide (SiO₂), pink variety likely colored by trace elements or microscopic inclusions
mineral
Ammolite
Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)
mineral
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Carved Mottled Greenish-Yellow Crystal/Glass Object
Unknown; possibly a form of quartz (chalcedony/jadeite/nephrite) or glass/resin.
Man-made Object/Uncertain Mineral
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Sedimentary Rock
Blue Agate (Dyed Chalcedony)
Silicon Dioxide (SiO2)
mineral
Green Druzy Quartz (Prasiolite)
Silicon Dioxide (SiO2) with inclusions (typically Chlorite or Actinolite)
mineral
Sandstone
Sandstone (Clastic Sedimentary Rock)
Sedimentary Rock
Goldstone
Not a natural mineral or rock. It is an ornamental glass.
Manufactured Glass (Simulant)
Agate Geode
Silicon Dioxide (SiO2) - Chalcedony / Quartz Variety
Mineral
Agate (or Banded Agate)
Agate (a variety of Chalcedony, which is a cryptocrystalline form of Quartz); Chemical Formula: SiO₂ (Silicon Dioxide)
Mineral, specifically a Cryptocrystalline Quartz variety
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Mixed Gemstone Beaded Jewelry
Various minerals (e.g., Quartz varieties like Rose Quartz, Amethyst; Peridot; Garnet; etc.)
Mineral
Golden Sheen Obsidian
Obsidian (volcanic glass) with inclusions of gas bubbles and mineral crystals (e.g., hematite, magnetite) causing the sheen
igneous
Banded Gneiss
Gneiss (pronounced "nice")
Metamorphic Rock
Black Tourmaline (Schorl)
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
mineral
Serpentine
Serpentine group minerals (e.g., Antigorite, Chrysotile, Lizardite). Chemical formula: (Mg, Fe)₃Si₂O₅(OH)₄
Mineral, often found as a rock (metamorphic)
Chrysoprase
Chalcedony (cryptocrystalline SiO2 variety)
Mineral
Halite (Rock Salt)
Halite; NaCl (Sodium Chloride)
Mineral
Schist
N/A (a rock type, not a mineral formula)
metamorphic